title: Elevated fatty acid synthase expression in prostate needle biopsy cores predicts upgraded Gleason score in radical prostatectomy specimens.
abstract: BACKGROUND
  We examined whether fatty acid synthase (FAS) expression in prostate biopsy cores had valuable information and could predict a Gleason score (GS) upgraded from biopsy to radical prostatectomy (RP) specimens.
  
  
  METHODS
  Immunostaining with a FAS antibody was performed on paraffin-embedded prostate biopsy cores with GS 5-6 obtained from 80 patients who subsequently underwent RP. The correlations between FAS expression and clinicopathological parameters, upgrading group, and clinicopathological parameters including FAS expression were analyzed. Logistic regression analysis was performed to identify a significant set of independent predictors for upgrading GS.
  
  
  RESULTS
  A total of 46 patients (57.5%) with biopsy GS 5-6 were upgraded to GS ≥7 at RP. FAS expression was significantly associated with clinical T stage (P = 0.0232) and positive core rate (P = 0.0245). Upgrading from biopsy GS 5-6 to GS ≥7 at RP was significantly associated with clinical T stage (P = 0.0337), positive core rate (P = 0.0262), and FAS expression (P < 0.0001). FAS expression was a significant predictor for upgrading from biopsy GS 5-6 to GS ≥7 at RP in multivariate analysis (P < 0.0001; odds ratio, 12.35). FAS scores showed the largest area under the receiver-operating characteristic curve (AUC) in preoperative parameters (AUC = 0.753).
  
  
  CONCLUSIONS
  Increased FAS expression in prostate biopsy cores could be a novel parameter for upgrading from biopsy GS 5-6 to GS ≥7 at RP. If a biopsy GS is low, the treatment strategy for patients with high FAS expression in prostate biopsy cores should be carefully determined.
authors.affiliation: Department of Urology, National Defense Medical College, Tokorozawa City, Saitama, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Hamada
authors.forename: Akio
authors.initials: A
authors.lastname: Horiguchi
authors.forename: Kenji
authors.initials: K
authors.lastname: Kuroda
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ito
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Asano
authors.forename: Kosuke
authors.initials: K
authors.lastname: Miyai
authors.forename: Keiichi
authors.initials: K
authors.lastname: Iwaya
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D001707:Biopsy, Needle / Q000379:methods; D054890:Fatty Acid Synthase, Type I / Q000096:biosynthesis*; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading / Q000379:methods; D011237:Predictive Value of Tests; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000201:enzymology* / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; C518729:FASN protein, human; D054890:Fatty Acid Synthase, Type I
keywords: Gleason score; biopsy cores; fatty acid synthase; upgrading